Switch arrangement



Aug. 12, 1958 P. B. c. VAN AMELSFORT 2,347,523

SWITCH ARRANGEMENT Filed Sept. 24, 1956 I NVENTOR PETRUS BERNAR CARO VAN A LS F0 R AG NT United States Patent SWITCH ARRANGEMENT Petrus Bernardus Carolus van Amelsfort, Eindhoven, Netherlands, assignor, by mesne assignments, to North American Philips Company, Inc., New York, N. Y., a corporation of Delaware Application September 24, 1956, Serial No. 611,436

Claims priority, application Netherlands October 18, 1955 Claims. (Cl. 200-11) The present invention relates. to switches. More particularly, the invention relates to rotary switchesQ In switches of the type of the present invention, which are adapted more particularly although not exclusively for high frequencies, at least a part of the contacts is constituted by a metal layer, e. g. a printed layer, which is provided according to a given pattern on or in an insulating supporting surface.

The present invention has for its object to provide a construction in which all the contacts, both the stationary and the movable contacts, consist of such a metal layer. In accordance with the invention, the movable contacts are constituted by a metal layer which is provided according to a given pattern on or in a flexible insulating plate and this layer is maintained pressed, by means of a compression spring provided at the other side of the plate, against the metal layer constituting the stationary contacts and provided on or in a stitf supporting layer.

In order that the invention may be readily carried into effect, it will now be described in detail with reference to the accompanying drawing, in which:

Fig. 1 is a schematic diagram in cross-section of an embodiment of the switch of the present invention;

Fig. 2 is a schematic diagram in plan of an embodiment of the switch of the present invention;

Fig. 3 is a schematic diagram of a portion of the embodiment of Fig. 2; and

Fig. 4 is a sectional view of a portion of the embodiment of Fig. 1

The device of Figs. 1 and 2 may constitute an element of the rotary wave-range switch of a radio receiver, which comprises a number of such elements. The switch element comprises a stiff insulating base plate 1, for example of hard paper, on or in which a metal layer 3 is provided according to a given pattern (see also Fig. 3). By means of a suitable known process, for example a photographic process, or by means of a templet,

said metal layer is precipitated on the plate 1 and made thicker and more wear resistant by electro-deposition.

As will be explained hereinafter, parts of the layer 3 constitute the stationary contacts of the switch element.

The movable contacts, in the present case rotary contacts, of the element are constituted by parts of a similar metal layer 5 (shown in dash lines in Fig. 3) which, however, is provided on a flexible insulating plate 7 according to a given pattern. The plate 7, with the layer 5 facing the layer 3, lies on the stiff plate 1 and the two layers are pressed together by means of two cupsprings 9 and 11 outside the plate 7, which are provided with radial slots and the edges of which are slightly bent back (Fig. 2). As is seen from Fig. 3, given parts of the layer 5 (shown in dash lines), which parts consequently act as contacts, interconnect several of the parts of the layer 3 which act as contacts.

The layer 3 is connected to a number of junctiontags constituted by hook-shaped metal wires 12 which are passed through the plate 1 and are connected by soldering to the several separated parts of the layer 3.

The plate 1 has a central round aperture 13 through which a hollow, non-round shaft 15, in the present case cross-shaped, extends so as to be movable without clearance in the aperture 13. The shaft 15 also passes through mating non-round central apertures of the plate 7, of the springs 9 and 11 and of two metal washers 17 and 19 (Figs. 1 and 2) between which last mentioned parts the assembly is clamped by Hanging the ends of the shaft 15.

Since the plate 7 is comparatively slack, at any rate considerably slacker than the plate 1, said plate 7, by the action of the cupsprings 9 and 11, follows all the irregularities of the stiff plate 1 and the two metal layers 3 and 5 remain pressed together under all conditions. In this connection, it has been found advantageous to provide the cupsprings 9 and 11 with radial slots in the aforesaid manner, since in this case the springs are each individually capable of exerting pressure at a comparatively great number of points and are consequently able to conform to any irregularities of the plate 1. The plate 1 should naturally be sufficiently stiff to prevent curving under pressure of the springs.

Fig. 4 shows in vertical cross-section, viewed in a radial direction, a part of the base plate 1 with the opposite part of the flexible plate 7. As is shown, the metal layer 3 is provided in the plate 1, while the metal layer 5 rests on the plate 7. As a matter of fact, it has been found desirable that one of the metal layers should project beyond the surface of the associated plate,

since if both layers are embedded said layers may engage each other insufliciently. If both layers are provided on the surface of the plates they tend to hook together so that the moment required for rotating the switch varies unduly. The manner of arranging the metal layers as shown in Fig. 4 is most practical, since there is sufiicient space for arranging the layer 3 in the comparatively thick plate 1. To accomplish this, the layer 3 may first be formed as a mirror image on a metal plate to which the layer does not firmlyadhere, and may sub sequently be pressed into the plate 1 after the plate 1 has been slightly softened by heating.

The rotor of the switch segment, that is the plate 7, together with a number of other similar rotors may be driven, for example by means of a fiat shaft (not shown) passing through the hollow shaft 15, the first-mentioned shaft being provided with a locking device in the usual manner. In order for the plate 7 to be driven by the shaft 15 the springs 9 and 11 should follow the plate 7- in the aforesaid manner.

While the invention has been described by means of a specific example and in a specific embodiment, I do not wish to be limited thereto, for obvious modifications will occur to those skilled in the art without departing from the spirit and scope of the invention.

What is claimed is:

1. A switching device comprising a first member of relatively stiff electrically insulating material, first contact means comprising a layer of electrically conducting material shaped in a predetermined pattern, means for supporting said first contact means by said first member, second member of relatively flexible electrically insulating material, second contact means comprising a layer of electrically conducting material shaped in a predetermined pattern, means for supporting said second contact means on said second member, means rotatively positioning said second member in cooperative relationship with said first member whereby said second contact means maintains contact with said first contact means, and spring means having a plurality of radially extending portions 3. for maintaining said second contact means in contact under pressure with said first contact means.

2. A switching device comprising a first member of relatively stiff electrically insulating material, first and second contact means each comprising a layer of electrically conducting material shaped in a predetermined pattern, a second member of relatively flexible elec-' trically insulating material, means for supporting one of said first and second contact means on one of said first and second members, means for embedding the other of said first and second contact means in the other of said first and second members, means rotatively positioning said second member in cooperative relationship With said first member whereby said first and second contact means maintain contact with each other, and spring means having a plurality of radially extending portions for maintaining said first and second contact means in contact with each other under pressure.

3. A switching device comprising a first member of relatively stifl? electrically insulating material, first and second contact means each comprising a layer of electrically conducting material shaped in a predetermined pattern, a second member of relatively flexible electrically insulating material, means for supporting one of said first and second contact means on one of said first and second members, means for embedding the other of said first and second contact means in the other of said members, means rotatively positioning said second member in cooperative relationship with said first member whereby said first and second contact means maintain contact with each other, spring means having a plurality of radially extending portions for maintaining said first and second contact means in contact with each other under pressure, and means supporting said spring means in conjoint relationship with said secondtmember.

4. A switching device comprising a first member of relatively stiff electrically insulating material, first and second contact means each comprising a layer of electrically conducting material shaped in a predetermined pattern, a second member of relatively flexible electrically insulating material, means for supporting one of said first and second contact means on one of said first and second members, means for embedding the other of said first and second contact means in the other of said first and second members, means rotatively positioning said second member in cooperative relationship with said first member whereby said first and second contact means maintain contact with each other, a cupspring having radially extending portions, and means supporting said cupspring in a manner whereby said second member is urged into contact With said first member thereby maintaining said first and second contact meansiin contact with each other under pressure.

5. A switching device comprising a first member of relatively stiff electrically insulating material, first and second contact means each comprising a layer of electrically conducting material shaped in a predetermined pattern, a second member of relatively flexible electrically insulating material, means for supporting one of said first and second contact means on one of said first and second members, means for embedding the other of said first and second contact means in the other of said first and second members, means rotatively positioning said second member in cooperative relationship with said first member whereby said first and second contact means maintain contact with each other, a cupspring having radially extending portions, means supporting said cupspring in a manner whereby said second member is urged into contact with said first member thereby maintaining said first and second contact meanstin contact with each other underpressure, and means for conjointly rotating said second member and said cupspring.

References Cited in the file of this patent UNITED STATES PATENTS 

